Tweak settings for size and image quality
Those settings come from looking at what obs does, including
- smaller bitrate
- gop_size = 250 (both raises quality and shrinks file size)
- time_base = 1/framerate most examples do that, with that is not necessary to tweak by hand streams framerates
- veryfast instead of ultrafast preset
There are still significant performance issues, makes the code more similar to existing examples, but as size and quality pretty much where we need